Universal electric induction heating and cooking element.



UNIVERSAL J. L. ANDERSON.

1112011110 lNDUCl'ION HEATING AND COOKING ELEMENT.

APELIUATION TILED 111111.12, 1912.

Patented Feb. 4, 1913.

2 SHEETS-SHEET 1.

Witnesses O0 OOOKDOOOO 0000 O OOOOOOCOCOO Attorneys Patented Feb. 4,1913.

2 SEEETS-SHEET 2.

Attorneys m inventor J. L. ANDERSON.

APPLIGATION FILED MAR.12, 1912.

UNIVERSAL ELECTRIC INDUCTION HEATING AND COOKING ELEMENT.

2 W7; /9 @1 0; @U/ W w 1 maximum degree and retained at the de-" JOHN L.ANDERSON. OF OGDEN, UTAH.

UNIVERSAL ELECTRIC INDUCTION HEATING AND COOKING ELEMENT.

Specification of Letters Patent.

Patented Feb. 4,] 91 3.

Original application filed October 30, 1911, Serial No. 657,574. Dividedand this application filed March 12, 1912. Serial No. 683,236.

also constitutes the secondary circuit of the same, the presentinvention being a divisional application of the application filedOctober 80, 1911, Serial No. 657,574.

A further object of the present invention isthe use of a transformer soconstructed and arranged as to be used as a cooking utensil, such as ahot plate or griddle, or as a sad iron, both of such elements beingprovided with means whereby the temperature may be regulated from aminimum to a sired degree, thus rendering a cooking utensil or sad ironthat is exceedingly useful and practical.

proceeds, the invention resides in the combination and arrangement ofparts and in the details of construction hereinafter described andclaimed, it being understood that changes in the precise embodiment ofinvention herein disclosed can be made Within the scope of what isclaimed without departing from the spirit of the invention.

In the drawingsFigure l is a top plan View of the element used as a hotplate or griddle. Fig. 2 is a section taken. on line 22 of Fig. 1.' Fig.3 is a longitudinal sectional view through a sad iron embodying thepresent invention. Fig. 1 is a section taken on line H of Fig. 3.

Referring to the drawings, and more particularly to the structure shownin Figs. 1 and 2, the numeral 1 designates the core which is composed ofsoft iron wire and is held in place by the circular retaining casing 2,an annular recess 3 being formed in the core, and into which is placedthe primary or .inducing winding or coil A fire proof insulating plate 5is provided, and

fitting over the coil 4, is an iron cover, griddle or heating plate 6.ielow this cover, is an annular non-magnetic plate or ring 7, which iswelded or brazed to the iron cover 6, the said plate or ring T beingmade of copper or brass, and fitting into the annular recess 8 of thecore 1. threaded as at 8 and has the top portion of the collar 9 of thecover fitted thereon. Thus by rotating the cover or plate 6, withrespect to the casing 2, said plate or cover is elevated with respect tothe core 1, thus varying the air gap therebetween. An insulating bushing10 is provided for the purpose of the passage of the flexible conductor11 which is properly insulated and is conneeted to any source ofelectrical energy.

The operation of the cooking utensil as shown in Figs. 1 and 2 is asfollows :The alternating current which impressed upon the primary coil 4produces a flow .of current in such coil, so that'said current in turnsets up an alternating magnetic field in the core 1. This magnetic fieldflows through the cover or plate 6, forming a link with thecircumferential edge thereof and the ring 7 thus inducing current oflarge value but low voltage in both the plate 6 and the ring 7. The heatgenerated by these secondary currents in the ring 7 is readilytransmitted to the plate 6, as said plate 6 and ring 7 are Welded orbrazed together as heretofore described. The direction of magnetic flowin the 'plate 6, is radially, and the direction of flow of the inducedor secondary current is parallel with the direction of current in theprimary coil 4:, or circumferentially around the plate 6. Thus byrotating the plate 6 relatively to the casing 2, and thus varying thedistance between the core 1 and the plate 6, the magnetic flux enteringthe plate 6, can be varied and consequently the induced or secondarycurrents. The heat generated in the plate 6 can therefore be varied atwill, the range of heat varying or rather shading from the minimum tothe maximum, similar to that of a gas burner.

The induction sad iron, as clearly shown in Figs. 3 and 4, is amodification of the induction hot plate or griddle, it requiring simplya few changes in the mechanical features to employ the same principle asheretofore set forth. In this instance, the heat is generated in thebase or sole 12 of the iron,

this sole being in reality the plate 6 as The casing 2 is shown in Figs.1 and 2. The core 13 is made or formed of a series of laminated sheetiron strips 14, while the shoe, sole or base 12 is composed of caststeel, and constitutes part of the magnetic circuit, and also thesecondary circuit of the transformer, this sole or base being the heattransmitting element. In this sole or base is placed the primary orinducing windin or coil 15, and brazed or welded to the inslde of thesole 12, is a nonmagnetic plate 16, which is composed of cop er orbrass. This plate fits in the recess of the core that is'also occupiedby the coil 15, the coil being retained in proper position and above thenon-magnetic plate lo-by the coil retainers 17. The screws l8 passthrough thecore 13'and engage the-,nut's 19 fitted 1n recesses]; at thebottom of the core 13 and thus provide a means for varying the magnetic,air gap as at, a, and consequently the heat generated by the sad iron.A stitt leaf spring 20 is provided to prevent vibration of the core,while the pressed steel housin 21incloses both the core and the coil.

Vhen it is desired to increase the air gap (1, the milled heads 22 areturned and thus the screws 18, .due ,tothe fixed position of the nuts19, cause the nuts to move upwardly and consequently raise the core 13and coill5.

From the foregoin description taken in connection with the rawings, itis evident that with a heating unit as herein set forth,

that the heat induced thereby may be regulated to a nicety and retainedat'any desired degree, thus rendering a device-for cooking purposes asshown in Figs. 1 and 2 or a de- "yice in the form of a sad iron as shownin Figs. 3 and 4, exceedingly-desirable 'and practical, the adjustmentsfor producing the effect being readily accessible to'the oper star andwhereby such adjustment may be given to theelements at will and asdesired.

What is claimed is 1. An electric induction heating element,

having an envelop, a transformer disposed therein having an air gap, andforming the heating unit, and means for varying the alr gap of thetransformer to regulate the de' gree of temperature generated in theelement.

2. An electric induction heating element, having a casing, a transformerforming the heating unit therefor mounted in said casing and having acore,fa coil and a heating plate, and means forj'varyin the relation ofsaid plate to the core and coi to regulate the degree of heat generated.

3,, An electric induction heating element,

havingia; casing, a transformer forming the heating unit. therefordisposed within the a casing and having a core, coil and a heatingplate, a magnetic plate forming the heat transmitter, and means forvaryin the relation. of. said plate:to the core an coil and consequentlythe d e ree of heat generated.

4:. An electric in uction heating element,

having a casing, a transformer forming the heating unit disposed withinthe casing and having a core, coil. and a heating'plate, a

magnetic plateforming the heat transmitter, anon-magnetic elementcarried by said magnetic late and opposed tothe core, and

means for varying the air gap between the non-magnetic element and thecore.

' 5. An electric induction heating element,

having" a casing, a coil and core disposed therein and providin arecess'adjacent to the core, a heatingp ate of magnetic metal connectedto the casing, a non-magnetic-ring carried by the heating plate: andfitting in said recess, and means for varying the air gap between thenon-magnetic ring and the core.

6. An electric induction heating element, having a casing a coil andcore disposed therein and provldinga recess adjacent to the core, aheating plate of a magneticmetal closing the casing, a non-magnetic ringcarried by the heating plate and fitting in said recess, and means foradjustably connecting the heating plate to the casing and for varyingthe air gap between the non-magnetic ring and the core.

In testimony that I claim the foregoing as my own, I have hereto affixedmy signature in the presence pf two witnesses. JOHN L. AND'E'RsoN.

Witnesses:

G. V. ZINN, D. \V. Ennis.

